Fluid heater



W. INNES FLUID HEATER Filed March 19'. 1921 INVENTOR 6 MTToRNEYs Patented Dec. 25, 1928.

UNITED STATES 1,696,305 PATENT OFFICE.

- wILLmia turns, on NORTHTTMBERLAND, ENGLAND, ASSIGNORTO m BABcocx & wILcox commnr, or BAYONNE, NEW JERSEY, A conronarron on NEW JERSEY.

FLUID HEATER.

\ AppUeati oniflledKarc-h 19,1921, Serial No. 453,764,,and in Great Britain March 24, 1920.

This invention relates to fluid, heaters or economizers a plicable to water tube steam generators of t 1e Babcock & l/Vilcox type and has for its object to provide an improved ar 5 rangement of such economizers whereby a better circulation through such econoinizers,

and greater ease in removing sedimentwith the use of smaller quantities of water than otherwise necessary are obtained.

In accordance with the invention the economizer is preferably soarrangedthat the cold water enters a series of headers from an upper box at one end and leaves by an upper box connected to the series oi headers at the other end, a bottom box not directly in the path of normal circulation being also provided for the removal of sediment.

The invention is illustrated in the accompanying drawing which shows, in longitudinal sectionthe lmproved feed water heater and other parts hereinafter referred to applied to a Babcock & Wilcox steam generator of the marine type.

Referring to thedrawing, thefeed water heater or economizer comprises a number of inclined tubes A connected at their ends to series of uptake and downtake headers B and C, respectively. Theheaders G are all joined at the top to a box D, the headers B being also all joined at thetop to abox E. At the lower end of the headers C is provided a box D, having a blow off connection (1. An inlet pipe, d, preferably fitted with a, feed or con trol valve, is connected to the box D, into 35 which box D the feed water is pumped and from which it passes through the tubes A in which it is heated by the waste gases of combustion on their way to the uptake or chimney, to the box E whence itis led by Way of a pipe G, from which it'is delivered preferably'through a non-return valve H into the steam and water drum F.

Since the lower box D is not directly in the path of the water circulation, the blowing down may be efiected at a point remote from i moved with a smaller quantity of water than would be the case with construct-ions inwhich the blow-down valves are fitted to the'inlet mal boiler operation, the bulk of the water blown out is supplied direct from the feed pump and is wasted, as it does not remove the sediment from the economizer.

; The heater or economizer maybe located the inlet and the sediment more effectively rebox and in which, when operated during nor-,

in any suitable position in the path of the waste gases. In the arrangement shown. the heateroit economizer is located directlyabove the generator, withthe tubes A slightly inclined to the horizontal, and headers 13 and C slightly inclined to the vertical, so as to allow the air to get away from the heater or econonizer.

The heater or economizer 1s encased as shown, the casing being provided with access doors Land is also partially rooted in at J i and separated from the boiler furnace K by a horizontal partition while baflies M are provided, whereby the gases are caused to follow the path indicated by arrows on their way to the uptake or chimney.

The generator pi'operwvh ch is illustrated as a Babcocl; 8; ivilcoxboiler, isshown as provided with horizontally inclined generating tubes divided into three spaced banks R, It and R connected at one end. touptake headers S, which are in turn connected to the steam and water drum F by horizontal tubes T, the opposite ends of the generating tubes being connected to a downtake header S nipplcd to the steam and water drum as at U. The are directed across the genera;- ing tubes by baffles V, a roof battle 7 preferably being disposed abovethe lower bank R oi the boiler tubes. The superheatcris preferably located in the space between the banks B and R and is shown as extending across the firstand second'passes ofthe boiler. The super-heater comprises U tubes N extending transversely of the boiler and connected at their ends to headers 'O, the upper one of which is provided with a transverse diaphragm P, so that the steam flows through the superhcater as indicated by the small arrows.

1n the form of economizer shown there is a c1rculat1on of water wlthin the economizer due to the action of the hot gases flowing over the economizer which tends to equalize the temperature of the water throughout the economizer. By supplying feed water to the upper portion. of the economizer in't-he way described the Water fed to the economizer is mingled more effectively with the water in the economizer through the action of the circulation caused by the heating action of the gases than it would be should the feed water enter the lower part of the economizer. By supplying feed Water to the upper portion of the 5 economizer in the way described the temperature of the water in the upper and lower tubes is therefore much more nearly equalized than in the case of an economizer of the class described in which the feed water is supplied to the lower part of the economizer.

Referring to the particular arrangement of econoinizer with horizontally inclined tubes with uptake and downtake end headers, if the feed water is supplied to the blowoif drum there is a very unequal distribution of heat in the eeonomizer tubes, the water in the lower tubes being much colder than that'in the upper ones. This unequal temperature results in unequal expansion between the top and bottom tubes, which causes the tubes to creep somewhat in their seats in the headers, thereby causing the water to leak to the outside, where it comes in contact with soot which may have settled on the tubes, and setting up active external corrosion. I have found, in actual installations, that where the econolnizer was built in this manner, in some cases the tubes had been corroded through from the outside and that the rear face of the header into which the tubes were expanded had also corroded away so that the seat was thinned down to a dangerous extent. Supplying the feed water to the top of the rear headers has the effect of equalizing the temperature over the whole of the tubes, and from careful readings which I have taken, I have found that the temperature of the water in all of the tubes is very much the sa1nein practice, I have not found a difference of more than 10 degrees F.-and by constructing the economizer in this manner, I have overcome leakage through the tubes C, so that the soot is kept dry and is readily blown from the tubes.

What Iclaim and desire to secure by Letters Patent of the United States is:

1. The combination with a steam boiler,

of an economizer heated by the gases leaving the boiler, said economizer having vertically extending headers at both ends thereof connected by horizontally disposed tubes, an inlet connection for feeding all of the water supplied to the boiler into the upper ends of all the inlet headers, an outlet connection for feeding to the boiler the water from the same ends of the outlet headers as it enters the inlet headers, said inlet and outlet headers being unconnected except through said tubes, an economizer setting for receiving the gases from the boiler and directing them over said economizer tubes and in a general direction from the outlet ofthe economizer towards the inlet thereof.

2. The combination with a. steam boiler, of an econolnizer heated by the gases leaving the boiler, said economizer having vertically extending headers at both ends thereof connected by horizontally disposed tubes, an inlet connection for feeding all of the water supplied to the boiler into the upper ends of the inlet headers at one end of said economizer, and outlet connection for feeding the water from the upper ends of the outlet headers to the boiler, said inlet and outlet headers being unconnected except through said tubes, and an eeononiizer setting for receiving the gases from the boiler and directing them over the tubes of said economizer.

3. The combination with a steam boiler. of an economizer heated by the gases leaving the boiler, said economizer having vertically extending headers at both ends thereof connected by horizontally disposer] tubes, an in let connection for feeding all of the water supplied to the boiler into the upper ends of the inlet headers of said economizer, an outlet connection for feeding the water from the upper ends of the outlet headers at the other ends of the economizer to the boiler, said inlet and outlet headers being unconnected except through said tubes, an economizer setting for receiving the gases from the boiler and directing them over the tubes of said economize! and in a general direction from the outlet of the economizcr towards the inlet thereof, and a blow-off connected to the lower part of the eeonomizcr.

In testimony whereof I have hereunto signed my name.

WILLIAM INNES. 

